There aren't a lot of Bodyweight purists out there. Many of them lift weights to some degree. Yet it’s surprising how many claim to be BW only and embrace kettlebell training. I suppose that a lot of the BW guys out there are anti-gym establishment, like the crew that revived kettlebells as a legitimate training too are. Plus, Pavel is quick to point out the effectiveness of BW training even though he promotes kettlebells. The acceptance of BW training on behalf of the kettle krew along with the anti-establishment mentality has apparently made it acceptable to train with kettlebells.
I don’t and haven’t trained with kettlebells. I don’t train with them for much of the same reason that I don’t train with any other weights: They cost money and I can’t travel with them. Also, I think that some of the kettlebell exercise border too closely on dangerous. Swinging a massive piece of iron by a towel just doesn’t strike me as safe. I have said previously that I don’t like exercises that are so close to injurious that one flaw in execution can mean injury. Sure, if you have the proper form you won’t get hurt but we all know that form can slip a bit when you fatigue.
I also don’t see anything magical about them either. They are a cannonball with a handle. The kettlebell is the child of improvisation, not of magic. It is simply an awkward weight which requires more stabilizer muscles to lift properly. That may make them a better workout than barbells, dumb bells and machines but you could replicate this awkwardness with sandbags, rocks, logs, or any other heavy, awkward object without spending the money on the glorified cannonball.
I may be coming down negatively on kettlebell training but I see them as a lot of hype and even a bit gimmicky. If you like training with them then by all means indulge. You certainly don’t need my non-expert endorsement to do so. I’d rather see you do this than nothing at all. Still, I’m about getting away from equipment and not relying on anything outside of my own body and mind to get myself in shape and kettlebells don't fit into the equation.